Everyone knows Beethoven wrote nine symphonies, right? Or did he? Undiscovered manuscripts keep popping up all the time. Uncovering a lost 10th symphony by Beethoven would surely give the classical music world something to shout about.

It could happen — at least it could according to our colleagues over at Weekend Edition Sunday. Reporter Naomi Lewin carefully unfolds the mysterious saga of a new Beethoven discovery, as a part of our April 1 news coverage.

Copyright 2012 National Public Radio. To see more, visit http://www.npr.org/.

Transcript

RACHEL MARTIN, HOST:

Mozart wrote 41 symphonies, and Haydn's official catalogue lists 104. But Beethoven, whose symphonies are among the most popular in the world, only composed nine - or so music historians have thought all these years. As Naomi Lewin of New York Public Radio reports, that number could soon change.

NAOMI LEWIN, BYLINE: The discovery of a symphony with Beethoven's name on it has set the music world on fire. Alan Gilbert is music director of the New York Philharmonic.

ALAN GILBERT: This is probably the biggest story to hit music in many years. I can't tell you how excited I am, and I am really looking forward to programming it at the New York Philharmonic.

LEWIN: Gilbert was stunned and a bit rueful at the earth-shaking news.

GILBERT: The nine symphonies of Beethoven are the iconic canon of symphonic repertoire. And many composers such as Mahler were unable to even go on after writing his ninth symphony because there was something that, something superstitious he felt about the fact that Beethoven only managed nine. But now, there's evidence that all of this angst and energy spent was wasted because Beethoven did in fact write a 10th symphony.

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FRIEDRICH VON UND ZUM HAGEN: The piano sketch for a Beethoven symphony was not what I expected to find on my trip to America.

LEWIN: Friedrich von und Zum Hagen is a professor of musicology at the University of Ostwestfalen, located in the same German state where Beethoven was born. Zum Hagen was in New York doing research on the inventions of Beethoven's friend, Johann Nepomuk Maelzl, the man who patented the metronome. Beethoven poked fun at that in his eighth symphony.

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LEWIN: Maelzl invented a slew of automated devices, and made a fortune exhibiting them all over America. In 1832, he set up shop in New York, at the Masonic Hall, and that's where the discovery of this new manuscript took place. Masonic Hall has moved since Maelzl's day, but it still contains a library. Glass cases display ritual jewelry and swords; nestled in a locked cabinet, there's a letter from freemason George Washington. Library director Tom Savini says the collection is carefully catalogued and yet...

TOM SAVINI: Sometimes, we just don't know what we're going to find in our files.

LEWIN: Professor Zum Hagen was looking for anything Maelzl might have left behind.

HAGEN: You can imagine how shocked I was when I saw a folder, and on it was the name on it Johann Nepomuk Maelzl. And when I looked inside I saw a symphony. And in Maelzl's handwriting it said: Ludwig van Beethoven. I said how can this be? And then I remembered an edition of the Journal of the Franklin Institute from 1827. And in it was written: He has also invented an apparatus which is attached to a pianoforte by which any piece of music which is played on it is at the same time correctly written out.

LEWIN: Zum Hagen thinks Maelzl asked Beethoven to try out the transcribing piano, since the composer was very enthusiastic about technical advances. He even speculates that Maelzl commissioned a symphony from Beethoven and then absconded to America with the manuscript.

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LEWIN: Professor Zum Hagen took his find to Alan Gilbert, who made a connection to Gustav Mahler. Mahler also served as music director of the New York Philharmonic right around the time the current Masonic Hall was being built. Gilbert suspects Mahler saw the score to Beethoven's 10th while the library was in transition.

GILBERT: Because there's some evidence that he might have incorporated some of the melodic material into the end of his ninth symphony.

LEWIN: Late Beethoven was fairly harmonically advanced.

GILBERT: Once again, I think Beethoven has come up with melodic material that will be resonating throughout the ages.

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LEWIN: The Masonic Library only contained two movements of Beethoven's tenth. Professor Zum Hagen is now on the hunt for the rest of the piece, following Maelzl's trail.

HAGEN: He traveled as far north as Canada, and as far west as Cincinnati. I hope to look in all the North American cities he visited before my U.S. visa expires one year from today.

LEWIN: For NPR News, I'm Naomi Lewin.

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MARTIN: And on this April's Fools Day, you are listening to WEEKEND EDITION from NPR News. Transcript provided by NPR, Copyright National Public Radio.